Handling pressure tar



, July 27 1926. F 1,

' H E. 'E. BARTELS ET AL I HANDLING PRES SURE TAR Filed Sept. 22,- 1924 05 (/42- Seflled Pressure 7771'- Pgrmqnni 2.5- fiver? 071g Fcfwarrz/ifiariez Patented July 21, was.

uul'rsnfsrar 1,524,038 that i EDWARD E. BARTELS AND EDWARD J. SEAEFFER, W'HITING, INDIANA, ASSIGNOBS TO STANDARD OIL COMPANY, OF WRITING, INDIANA, AND CHICAGO, ILLINOIS, A.

CORPORATION OF INDIANA.

naunnmo reassures ran.

.2 Application filed September 22, 19%. Serial 1%. 739,108.

The handling of pressure tar or the un-- distilled residuum from pressure cracking,

processes presents great difficulties, particularly in its redistillation either in continuous stills or coking stills, by reason of the large amounts of sediment which tends to deposit from the pressure tar. This sediment in coking processes, for example, frequently necessitates transferring entire batches of pressure tar undergoing distillation from one still to another by reason of excessive formation of coke and resulting hotbottoms in such stills.

The present invention relates to the handling of pressure tar in such a manner as to avoid such ditlicultics during the distillation of the tar, and to ren'druseful the sedimentary matter deposited by the pressure tar. It will be fully understood from the following description, illustrated by the accompanying drawings, in which:

Figure 1 illustrates diagrammatically a system of tanks and connections employed in carrying out the present invention; and

Fig. 2 is a diagrammatic sectional view through one of the tanks of the series.

In carrying out the present invention, a plurality of tanks are employed fer receiving the pressure tarfrom the pressure cracking system. For example, as shown diagrammatically in Fig. 1, three tanks ofthis character may be employed, designated 12 ota pump 13, by which pressure tardrawn from a selected one of the tanks is forced through line 14 to the still (not shown). 'In operation, the tanks A, B and C are each in succession filled, permitted to settle and the pressure tar separated, and the separated clean pressure tar pumped to the pressure tar stills; Thus, while the tank A is being filled with pressure tar, that in the tank B is being allowed to settle, and that in the tank C is being drawn off by the pump 13. Rates of pumping are approximately adjusted "so that, when tank C is empty, tank A is approximately filled. The pressure tar in tank A is permitted to settle, the

settled pressure. tar in tank 13 is drawn as ,(listiuct layers, upper layer 15 oi settled or clean pressure tar. a layer 16 of sediment or B. 53., and layer 17 of thickeror heavier sediment, designated permanent B. SF. Tue pressure tar contains from 3 to 5% of materials which deposit in the two lower layers or sediment. These are allowed to accumulate until the upper surface of the upper layer at? sediment 16 approaches a short distance, 6 to' 8 inches, of the draw-oft line for settled pressure tar, for example, the line 9 in the case of tank A. This line is elevated a considerable distance, say 4: to 16 inches above the bottom of the tank. mentis then drawn oil through lower pipe 18, in the case of tank A, passing to the manifold suction line 19 of pump 20, by which the B. S. is pumped to the mixing tank 21. l3. S.flX'&WOfi lines 22 and 23 are provided for tanks B and C, respectively, corresponding to line 18 of tank A and con nee-ting with the line it).

After a quantity of the sedimentor B. S. 16 hascollected in any one of the tanks, it is drawn out through the proper line, 18, 22 or 23, and tor-cod by the pump into the mix- .ing tank 21. Into this tank a suitable quantity of heavy oil having a density of at least one, and preferably mi from 1.03 to 1.07 is forced through line as into the tank 21. Oils suitable for this purpose are,,tor example, the road oils and rinsing oils obtained by steam reduction of pressure tar;

Such oils have a density of 1.00 and higher The intermediate layer 16 of sedito deposit sediment on. settling, and "to he used as fuel oil;

excellently adaptdfor us as heavy fuel It is readily apparent that the sediment may be removed from the pressure tar by centrifuging or by other suitable means instead of by gravity settling.

We claim:

1. The method of handling pressure tar comprising settling the pressure tar, separately removing the settledtar and the sediment, and admixingthe latter with a heavy oil having a specific gravity of at least lat 2. The methodpf handling pressure tar comprising removing separable sediment from the pressure tar and admixing the sediment with a heavy oil having a specific gravity of at least 1 at 60 F.

3! The method of handling pressure tar comprising the steps of settling the pressure tar, separately removing thesettled pressure tar and the sediment, and admixing the latter with a residuum from distillat an of pressure tar, said residuum having aspecifie gravity of at least 1.00 and aviseosity 1.5 to 6 Engler at 212 F.

4. The method of forming a fuel oil mixture which comprises admixing pressure tar B. S'. with a heavy oil having a density of at least 1.00. 1

EDl/VARD E. BARTELS. EDWARD SHAEFFER. 

